Table 2.

Histological patterns analyzed in hip replacement failures due to ALTR

Histological Pattern	Characteristics
Macrophagic Pattern	Macrophagic infiltrate (grade ≥ 1) without or with minimal evidence of interstitial and/or perivascular lymphocytic infiltrate (<grade 1)
Mixed Macrophagic and Lymphocytic Pattern w/wo Plasmacytic Component	Macrophagic (grade ≥ 1) and lymphocytic (grade ≥ 1) infiltrate
Without Presence of Germinal Centers or Eosinophils
With Presence of Germinal Centers or Eosinophils
Granulomatous Pattern	Any pattern with predominant presence of sarcoid-like granulomas
Lymphocytic Pattern	Interstitial and/or perivascular lymphocytic infiltrate without evidence of macrophagic infiltrate